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Malaysia vows: We will give plane families closure
Australia's prime minister said everything that possibly could be done to find the plane would be done, but cautioned, "We cannot be certain of success."
Najib's wife, Rosmah Mansor, also traveled to Perth, where she met with Danica Weeks, whose husband, Paul Weeks, was among those on Flight 370. Weeks said the meeting gave her some comfort and confidence the Malaysians are committed to finding answers. But she also said the pervasive uncertainty surrounding the plane's fate had made coping with the loss impossible.
"You cannot grieve for someone unless you have something concrete," Weeks told Australia's Channel 9.
Two British vessels — a nuclear-powered submarine with advanced underwater search capability and the British Survey ship HMS Echo — have joined the hunt, Houston said. The Ocean Shield, an Australian warship carrying a U.S. device that detects "pings" from the plane's flight recorders, was en route.
Spotting wreckage is key to narrowing the search area and ultimately finding the plane's data recorders, which would provide a wealth of information about the condition the plane was flying under and the communications or sounds in the cockpit.
The data recorders emit a ping that can be detected by special equipment in the immediate vicinity. But the battery-powered devices stop transmitting the pings about 30 days after a crash. Locating the data recorders and wreckage after that is possible, but becomes an even more daunting task.
Ng reported from Kuala Lumpur, Malaysia. Associated Press writers Rod McGuirk in Canberra, Australia, and Kristen Gelineau and Rohan Sullivan in Sydney contributed to this report.